public String generatePieChart(
String hitOrdNum, HttpSession session, PrintWriter pw, String courseId, int studentId) {
/* int groupId=0;
if (groupName.equals("All")){
groupId=0;
}else{
groupId = studStatisticBean.getGroupIdByName(groupName);
}*/
String filename = null;
try {
// Retrieve list of WebHits
StudentsConceptChartDataSet whDataSet =
new StudentsConceptChartDataSet(studStatisticBean, courseId, studentId);
ArrayList list = whDataSet.getDataBySection(hitOrdNum);
// Throw a custom NoDataException if there is no data
if (list.size() == 0) {
System.out.println("No data has been found");
throw new NoDataException();
}
// Create and populate a PieDataSet
DefaultPieDataset data = new DefaultPieDataset();
Iterator iter = list.listIterator();
while (iter.hasNext()) {
StudentsConceptHit wh = (StudentsConceptHit) iter.next();
data.setValue(wh.getSection(), wh.getHitDegree());
}
// Create the chart object
PiePlot plot = new PiePlot(data);
plot.setInsets(new Insets(0, 5, 5, 5));
plot.setURLGenerator(new StandardPieURLGenerator("xy_chart.jsp", "section"));
plot.setToolTipGenerator(new StandardPieItemLabelGenerator());
JFreeChart chart = new JFreeChart("", JFreeChart.DEFAULT_TITLE_FONT, plot, true);
chart.setBackgroundPaint(java.awt.Color.white);
// Write the chart image to the temporary directory
ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());
filename = ServletUtilities.saveChartAsPNG(chart, 600, 400, info, session);
// Write the image map to the PrintWriter
ChartUtilities.writeImageMap(pw, filename, info);
pw.flush();
} catch (NoDataException e) {
System.out.println(e.toString());
filename = "public_nodata_500x300.png";
} catch (Exception e) {
System.out.println("Exception - " + e.toString());
e.printStackTrace(System.out);
filename = "public_error_500x300.png";
}
return filename;
}
protected void buildChart() {
DefaultCategoryDataset dataset = new DefaultCategoryDataset();
chart =
ChartFactory.createMultiplePieChart(
"Untitled Chart", dataset, org.jfree.util.TableOrder.BY_COLUMN, false, true, false);
chart.setAntiAlias(true);
// chartPanel = new ScrollableChartPanel(chart, true);
chartPanel = buildChartPanel(chart);
// chartHolder.getViewport().setView(chartPanel);
setChartPanel(chartPanel);
JFreeChart baseChart = (JFreeChart) ((MultiplePiePlot) (chart.getPlot())).getPieChart();
PiePlot base = (PiePlot) (baseChart.getPlot());
base.setIgnoreZeroValues(true);
base.setLabelOutlinePaint(java.awt.Color.WHITE);
base.setLabelShadowPaint(java.awt.Color.WHITE);
base.setMaximumLabelWidth(
0.25); // allow bigger labels by a bit (this will make the chart smaller)
base.setInteriorGap(0.000); // allow stretch to compensate for the bigger label width
base.setLabelBackgroundPaint(java.awt.Color.WHITE);
base.setOutlinePaint(null);
base.setBackgroundPaint(null);
base.setShadowPaint(null);
base.setSimpleLabels(false); // I think they're false anyway
// change the look of the series title to be smaller
StandardChartTheme theme = new StandardChartTheme("Hi");
TextTitle title = new TextTitle("Whatever", theme.getLargeFont());
title.setPaint(theme.getAxisLabelPaint());
title.setPosition(RectangleEdge.BOTTOM);
baseChart.setTitle(title);
// this must come last because the chart must exist for us to set its dataset
setSeriesDataset(dataset);
}